Dental biofilm and laboratory microbial culture model for cariology research

Abstract

Objectives: This paper aims to review the common bacteria biofilms and in vitro biofilm models used in recent laboratory studies for cariology research. Methods: A search in the Web of Science from using the keywords (demineralization OR remineralization) AND (dental caries) from 2000 to 2016. The title and abstract of potentially eligible publications were screened. Reviews and irrelevant studies such as those on bone studies were excluded. The remaining publications were laboratory studies and studies using microbial culture models were included in this review. Results: The common bacteria biofilms used were plaque microcosm from natural oral microflora and defined-species biofilm consortia with cariogenic bacteria. The common cariogenic bacteria were Streptococci, Actinomycetes and Lactobacilli. These bacteria dominantly proliferated in the dental biofilm collected from carious lesion and they were found to be more closely associated than the other bacteria. The laboratory microbial culture models could be categorized into closed system and open system. Agar plate and microtiter biofilm model were the two common microbial culture models in the closed system. These models had a finite supply of nutrient. Common microbial culture models in the open system included chemostat, flow cell biofilm model, constant depth film fermenter model, drip flow biofilm reactor, perfused biofilm fermenters and artificial mouth model. These models enabled the supply of fresh culture medium, and allowed removal of metabolites and spent culture liquid simultaneously. They simulated the in vivo environment better than those in closed system. They also provided better regulation of biofilm growth rate and other variables. Conclusions: Streptococci, Actinomycetes and Lactobacilli were the three common cariogenic bacteria used in recent laboratory studies for cariology research. Several common microbial culture models were used and they could be categorized into closed system and open system.